Rice false smut occurs in all rice areas. In the infected rice ear, the open rate increases, the 1000-grain weight decreases, the broken rice increases, affecting the yield (generally reducing production by 5%-10%) and quality. A large amount of food also has a certain impact on human health. Timely pesticide control is critical. Pneumatic Control Valve,Flow Control Valve,Control Valve M Profile Press Fittings Co., Ltd. , http://www.nspipefitting.com
Symptoms of the disease: Rice is mainly susceptible to heading and flowering, and the pathogen damages the upper grain of the ear. The diseased grain reveals a yellowish-green small sclerotium at the joint of the glume, and the sclerotium envelops and wraps the whole hull; it is black-green, the surface is smooth, and finally cracks, emitting black-green powder.
Incidence conditions:
(1) It is rainy and illuminating in the rice rupture, the initial spike and the flowering stage, and the relative humidity is too high, which is beneficial to the pathogenesis of rice false smut. The bacteria develop well at a temperature of 24-32 ° C, and the optimum temperature is 28 ° C. Below 12 ° C, above 36 ° C can not grow.
(2) The degree of disease of different rice varieties is very different. Generally, tight-ear type or late-maturing varieties are easy to develop, while scattered-early type early-maturing varieties are mild.
(3) Different fertilization methods have different incidences. Under the same fertilization amount, the condition is aggravated with the increase of panicle fertilizer. In addition, partial application of nitrogen fertilizer, deep water irrigation, field water layer fall too late and serious.
Pesticides Network Xiaobian teaches you how to prevent and control:
(1) Select disease-resistant varieties and establish disease-free seed fields.
(2) Improve the cultivation measures, make rational fertilization, increase the application of phosphorus and potassium fertilizer, prevent the late application of nitrogen fertilizer, excessive, excessive panicle fertilizer, and the water layer is too deep. Promote rare planting, less seedlings and strong plants, improve ventilation and light transmission conditions. Do a good job of turning the ground in autumn and burying the pathogens in the soil.
(3) Seed soaking with 50% fungicide carbendazim 1000 times solution for 48-72 hours. 7-10 days before rice heading, using 6% chlorhexone powder 1.5-2 kg per acre or 150 g of DT fungicide, spraying 50 kg of water, the control effect is very good.
Occurrence and prevention of rice false smut